I will give u understanding but what u do with it is up to u. I must start from the beggining. God put man in a place that He knew would be full of sin and suffering because He wants something. God created men and angels in His image. God is a spirit being. Men and angels r spirit beings trapped inside a body. The differences between men and angels r; angels have a different body and they have power and authority which men have no power and little authority. When God created the angels He created them like the military but instead of rank He gave them power and authority, from the least in power and authority up to and including God's generals or archangels. I believe Lucifer was God's 5 star general. Lucifer and 1/3 of the angels rebelled because they WANTED what God would not allow and they WANTED it MORE than they WANTED God. If they would have WANTED God MOST then they would not have rebelled. We r here because of what they did. We r here to be tested and tried, molded and made ready for heaven. God will have no more rebellion in His kingdom. If we can serve god no matter the cost like Job and Joseph ( Go through the fire). If we can surrender our will and do God's will for our lives (Take up our cross). If we can say no to self, sin and the world here while being tempted (Overcome). If we can do all this here then when in heaven we will have no problem serving and obeying God. God will not just zap us and make us to where we will never sin nor rebel against Him. If He were to do this He would be programming us and we would be no more than robots and no longer free willed. You say there will be no tempter in heaven. That is correct but u will still WANT. WANT is why the angels rebelled and why we sin. The bible teaches that we r tempted when we r drawn away becasue of our own lust. It is something that we WANT. You cannot be tempted by something that u truly care nothing for. We must overcome self ( WANT-or what the bible terms the flesh). When God created men and angels He gave them a spiritual heart that is the center of our being. It is located in the lower left side of our chest. Proverbs 4:23 (Keep your heart with all diligence; for out of it r the issues of life). When I read this verse I started watching what went on in and around my heart and God has given me understandin. The spiritual heart is where emotions and desires dwll in us, it is where God's spirit dwells in us or the where the inborn nature dwells in us and which ever dwells is in our heart will controll us. The inborn nature is nothing more than a fallen angel of the least power and authority. He does not have the power to possess u as in demonic possession. To possesss u as in demonic possession it requires several of the least in power and authority with their combined power or one of a higher power. But they do controll us. They raise up emotions and desires, give us feelings, urges and impressions, and they put thoughts into our head. If u will take note (watch ur heart) u will see that there is a motive behind most that we say, do and think. Do we say, do and think because of lust, greed, envy, jealousy, anger, pride, hatred etc. or do we say, do and think becasue of love, compassion and long suffering etc? What is in our heart will come out in word thought and or deed. When God's spirit comes into our heart He casts out this inb9orn nature and with it goes bad emotions like greed etc. because Gid will not dwell where sin dwells. When these bad emotions r no longer in our heart they no longer controll us it is how God makes it possible to say no to sin. The inborn nature is still with us and will still raise up emotions, desires etc. and try to get us to sin. We can give into an emotion and it will come back into our heart and the inborn nature will controll us with it. We must repent and ask God to cleanse our heat again. God uses these fallen angels to test and try, mold and make us ready for heaven. God also gave these fallen angel what they WANT but they must get what they want through us by expierencing what we expierence. I hope this helps u. watch what goes on in and around ur heart.
. But he really is a liar and demon 
